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BACKGROUND: Intravenous lipids are critical to the care of extremely premature and other high-risk infants. OBJECTIVES: This study evaluated safety and efficacy of parenteral nutrition (PN) with composite intravenous lipid emulsion (CO-ILE) with fish oil compared with pure soybean oil lipid emulsion (SOLE). METHODS: Randomized, controlled, double-blind, multicenter study (NCT02579265) in neonates/infants anticipated to require ≥28 d of PN due to gastrointestinal malformations or injury. Duration of the initial and extended treatment phase was 28 d and 84 d, respectively (for patients with PN indication after day 28). RESULTS: Eighty-three patients (mean postnatal age 11.4 d, 54 preterm) received CO-ILE and 78 patients received SOLE (mean postnatal age 8.3 d, 59 preterm). Thirty-three patients per group completed 28 d of treatment. Risk of having conjugated bilirubin values >2 mg/dL confirmed by a second sample 7 d after the first during the initial treatment phase (primary outcome) was 2.4% (2 of 83) with CO-ILE and 3.8% (3 of 78) with SOLE (risk ratio: 0.59; 95% confidence interval [CI]: 0.09, 3.76). Between days 29 and 84, the number of patients with confirmed conjugated bilirubin values >2 mg/dL did not increase in the CO-ILE group (n = 2) and increased in the SOLE group (n = 9). At the end of the initial treatment phase, conjugated bilirubin concentrations were 45.6% lower under CO-ILE than under SOLE (P = 0.006). There was no clinical or laboratory evidence of essential fatty acid deficiency in patients in the CO-ILE group. Median time to discharge alive was 56.7 d and 66.4 d with CO-ILE and SOLE, respectively (hazard ratio: 1.16; 95% CI: 0.81, 1.68). CONCLUSIONS: CO-ILE was associated with a possible lower risk of cholestasis and significantly lower conjugated bilirubin concentration at the end of the initial treatment phase in high-risk neonates and infants as compared with patients treated with SOLE. In summary, these data indicate that CO-ILE can be considered safe and may be preferable over SOLE in high-risk neonates. This trial was registered at clinicaltrials.gov as NCT02579265.
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Immune checkpoint inhibitors are effective first-line therapy for solid cancers. However, low response rate and acquired resistance over time has led to the need for additional therapeutic options. Here, we evaluated synergistic antitumor efficacy of EGFR × MET targeting bispecific antibody, amivantamab with PD-L1 immunotherapy, pembrolizumab in head and neck squamous cell carcinoma (HNSCC) and lung squamous cell carcinoma tumor-bearing humanized patient-derived xenograft (PDX) models. We demonstrated that pembrolizumab or amivantamab alone was ineffective and that combination treatment induced a significant reduction of tumor growth in both models (P < 0.0001 and P < 0.01, respectively). It appeared that combination of amivantamab and pembrolizumab significantly enhanced infiltration of granzyme B-producing CD8 T cells was in the TME of HNSCC PDX (P < 0.01) and enhanced neoantigen-associated central memory CD8 T cells in circulating immune cells. Analysis of single-cell RNA transcriptomics suggested that the tumor cells dramatically upregulated EGFR and MET in response to PD-L1 immunotherapy, potentially creating a metabolic state fit for tumor persistence in the tumor microenvironment (TME) and rendered pembrolizumab ineffective. We demonstrated that EGFRHIGHMETHIGH subcluster displayed an increased expression of genes implicated in production of lactate [SLC16A3 and lactate dehydrogenase A (LDHA)] compared to the EGFRLOWMETLOW cluster. Accumulation of lactate in the TME has been associated with immunosuppression by hindering the infiltration of tumor killing CD8 T and NK cells. This study proved that amivantamab reduced glycolytic markers in the EGFRHIGHMETHIGH subcluster including SLC16A3 and LDHA and highlighted remodeling of the TME by combination treatment, providing rationale for additional therapy of amivantamab with PD-1 immunotherapy. SIGNIFICANCE: Amivantamab in synergy with pembrolizumab effectively eradicated EGFRHIGHMETHIGH tumor subcluster in the tumor microenvironment of head and neck squamous cell carcinoma and overcame resistance against anti-PD-1 immunotherapy.
Assuntos
Anticorpos Monoclonais Humanizados , Neoplasias Pulmonares , Carcinoma de Células Escamosas de Cabeça e Pescoço , Microambiente Tumoral , Humanos , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Animais , Camundongos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/imunologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Antígeno B7-H1/metabolismo , Linhagem Celular TumoralRESUMO
PURPOSE: Remote ischemic conditioning (RIC) is a maneuver involving brief cycles of ischemia reperfusion in an individual's limb. In the early stage of experimental NEC, RIC decreased intestinal injury and prolonged survival by counteracting the derangements in intestinal microcirculation. A single-center phase I study demonstrated that the performance of RIC was safe in neonates with NEC. The aim of this phase II RCT was to evaluate the safety and feasibility of RIC, to identify challenges in recruitment, retainment, and to inform a phase III RCT to evaluate efficacy. METHODS: RIC will be performed by trained research personnel and will consist of four cycles of limb ischemia (4-min via cuff inflation) followed by reperfusion (4-min via cuff deflation), repeated on two consecutive days post randomization. The primary endpoint of this RCT is feasibility and acceptability of recruiting and randomizing neonates within 24 h from NEC diagnosis as well as masking and completing the RIC intervention. RESULTS: We created a novel international consortium for this trial and created a consensus on the diagnostic criteria for NEC and protocol for the trial. The phase II multicenter-masked feasibility RCT will be conducted at 12 centers in Canada, USA, Sweden, The Netherlands, UK, and Spain. The inclusion criteria are: gestational age < 33 weeks, weight ≥ 750 g, NEC receiving medical treatment, and diagnosis established within previous 24 h. Neonates will be randomized to RIC (intervention) or no-RIC (control) and will continue to receive standard management of NEC. We expect to recruit and randomize 40% of eligible patients in the collaborating centers (78 patients; 39/arm) in 30 months. Bayesian methods will be used to combine uninformative prior distributions with the corresponding observed proportions from this trial to determine posterior distributions for parameters of feasibility. CONCLUSIONS: The newly established NEC consortium has generated novel data on NEC diagnosis and defined the feasibility parameters for the introduction of a novel treatment in NEC. This phase II RCT will inform a future phase III RCT to evaluate the efficacy and safety of RIC in early-stage NEC.
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Enterocolite Necrosante , Teorema de Bayes , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Enterocolite Necrosante/terapia , Estudos de Viabilidade , Humanos , Lactente , Recém-Nascido , Intestinos , Isquemia/terapia , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do TratamentoRESUMO
BACKGROUND: The Old-World bollworm, Helicoverpa armigera (Hübner), was recently documented attacking cotton and soybean plants in Brazil; however, restricted basic knowledge on host plant interactions and landscape use in Brazil have limited the effectiveness of control measures. In this study, we evaluated the suitability of different crops commonly cultivated in Brazil as hosts for H. armigera and H. zea, and examined their contribution to the establishment and size of H. armigera and H. zea field populations. We also estimated the proportions of H. armigera and H. zea moths that used cotton, noncotton C3 plants, and C4 plants as hosts in four regions in Brazil through the length of the cropping season. RESULTS: Viability of H. armigera larvae was highest on cotton (46.1%), followed by millet (39.5%), sorghum (31.2%), soybean (24.2%), and maize (21.1%). Noncotton C3 hosts served as the major source of H. armigera moths in all regions evaluated, and C4 hosts were a source of H. armigera mainly in regions where winter maize is typically cultivated. H. armigera moths that used cotton plants as natal hosts were observed during the reproductive stage of the crop mainly in the state of Bahia. Only C4 host plants were a consistent source of H. zea moths, primarily when maize was in the reproductive stage. H. armigera individuals were the main species infesting cotton and soybean fields while H. zea individuals were the main species infesting maize ears. CONCLUSIONS: Regional differences in the host use and population dynamics of H. armigera among the regions evaluated may be attributed to variation in alternative host utilization (crops, noncrops, and weeds) and the possible occurrence of facultative diapause and or migration.
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Lepidópteros , Mariposas , Animais , Brasil , Produtos Agrícolas , Humanos , Larva , Zea maysRESUMO
OBJECTIVE: This study aimed to examine the association between team stress level and adverse tracheal intubation (TI)-associated events during neonatal intubations. STUDY DESIGN: TIs from 10 academic neonatal intensive care units were analyzed. Team stress level was rated immediately after TI using a 7-point Likert scale (1 = high stress). Associations among team stress, adverse TI-associated events, and TI characteristics were evaluated. RESULT: In this study, 208 of 2,009 TIs (10%) had high stress levels (score < 4). Oxygenation failure, hemodynamic instability, and family presence were associated with high stress level. Video laryngoscopy and premedication were associated with lower stress levels. High stress level TIs were associated with adverse TI-associated event rates (31 vs. 16%, p < 0.001), which remained significant after adjusting for potential confounders including patient, provider, and practice factors associated with high stress (odds ratio: 1.90, 96% confidence interval: 1.36-2.67, p < 0.001). CONCLUSION: High team stress levels during TI were more frequently reported among TIs with adverse events.
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Unidades de Terapia Intensiva Neonatal , Intubação Intratraqueal/métodos , Equipe de Assistência ao Paciente , Estresse Psicológico , Competência Clínica/normas , Feminino , Humanos , Recém-Nascido , Intubação Intratraqueal/efeitos adversos , Laringoscopia , Masculino , Pré-Medicação , Estudos Retrospectivos , Análise e Desempenho de Tarefas , Estados UnidosRESUMO
OBJECTIVES: To investigate the correlation of serum total testosterone levels with International Prostate Symptom Score and prostate volume in aging men. METHODS: A cross-sectional study was conducted in 50 men who had participated in a medical examination. Prostate specific antigen levels, International Prostate Symptom Score, total/transitional prostate volume, body mass index, maximal flow rate, and serum total testosterone levels were evaluated. The correlation between serum total testosterone levels and additional parameters was statistically analyzed. RESULTS: The median age and total testosterone levels were 60.4 years (interquartile range: 55.0-68.0 years) and 4.3 ng/mL (interquartile range: 3.6-5.1 ng/mL), respectively. Total testosterone levels showed a significant negative correlation with body mass index, transitional prostate volume, International Prostate Symptom Score (including voiding/storage sub scores). On multivariate linear regression models, the total testosterone level was associated with body mass index and total International Prostate Symptom Score. CONCLUSIONS: As total testosterone levels decrease, both International Prostate Symptom Score and transitional prostate volume increase significantly. These findings provide evidence of the presence of more severe lower urinary tract symptoms and larger transitional prostate volume in aging men.
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Sintomas do Trato Urinário Inferior/patologia , Hiperplasia Prostática/patologia , Testosterona/metabolismo , Idoso , Índice de Massa Corporal , Estudos Transversais , Humanos , Sintomas do Trato Urinário Inferior/sangue , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Hiperplasia Prostática/sangue , Estudos Retrospectivos , Índice de Gravidade de DoençaRESUMO
NEC is a multifactorial disease that occurs when multiple risk factors and/or stressors overlap, leading to profound inflammation and intestinal injury. Human milk feedings, both from the infant's mother and donor human milk, have been associated with reductions in NEC in preterm infants. This article will review the protective factors in human milk, clinical studies of human milk and NEC, and practices to enhance human milk use in neonatal intensive care units.
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Enterocolite Necrosante/prevenção & controle , Doenças do Prematuro/prevenção & controle , Terapia Intensiva Neonatal/métodos , Leite Humano/química , Aleitamento Materno , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Unidades de Terapia Intensiva NeonatalRESUMO
Background After adrenalectomy, urinary fractionated metanephrine concentrations are expected to be reduced. However, there are few studies suggesting cut-offs for adrenalectomy patients. Methods Urinary metanephrine and normetanephrine concentrations in adrenalectomy patients and two controls were compared and hormonal concentrations were evaluated via time intervals after surgery. Results The median urinary metanephrine level after unilateral adrenalectomy was lower than that of the non-pheochromocytoma controls but comparable to healthy controls. Urinary normetanephrine concentrations did not differ between adrenalectomy patients and non-pheochromocytoma controls, although both group had levels higher than those of healthy controls. The median urinary normetanephrine level in the immediate postoperative period was higher than in the later period. Conclusions Urinary metanephrine concentrations were lower after adrenalectomy, but urinary normetanephrine concentrations were not changed compared with the non-pheochromocytoma controls. However, urinary normetanephrine concentrations in the patient group were higher than levels in the heathy controls.
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Neoplasias das Glândulas Suprarrenais/urina , Adrenalectomia/métodos , Metanefrina/urina , Normetanefrina/urina , Feocromocitoma/urina , Neoplasias das Glândulas Suprarrenais/patologia , Neoplasias das Glândulas Suprarrenais/cirurgia , Adulto , Biomarcadores/urina , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Feocromocitoma/patologia , Feocromocitoma/cirurgia , Período Pós-Operatório , Valores de ReferênciaRESUMO
BACKGROUND: The noctuid Helicoverpa armigera is one of the key cotton pests in the Old World. One possible pest regulation method may be the management of host crop in the landscapes. For polyphagous pests such as H. armigera, crop diversity and rotations can offer sequential and alternate resources that may enhance abundance. We explore the impact of landscape composition and host crop diversity on the abundance and natal host plant use of H. armigera in northern Benin. RESULTS: Host plant diversity at the largest scale examined (500 m diameter) was positively correlated with H. armigera abundance. Host plant diversity and the cover of tomato crops were the most important variables in relation to high abundance of H. armigera. Host plant (cotton, maize, tomato, sorghum) proportions and C3 versus C4 plants did not consistently correlate positively with H. armigera abundance. Moth proportion derived from cotton-fed larvae was low, 15% in 2011 and 11% in 2012, and not significantly related to H. armigera abundance. CONCLUSION: Cotton crop cover was not significantly related to H. armigera abundance and may be considered as a sink crop. Landscape composition and sequential availability of host plants should be considered as keys factors for further studies on H. armigera regulation. © 2015 Society of Chemical Industry.
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Gossypium/parasitologia , Mariposas/fisiologia , Animais , Benin , Produtos Agrícolas/parasitologia , Preferências Alimentares , Larva/fisiologia , Dinâmica PopulacionalRESUMO
BACKGROUND: Nonsteroidal anti-inflammatory drugs (NSAIDs) have been shown to inhibit several pathways in experimental models of breast carcinogenesis, but epidemiological evidence remains insufficient to support their use for breast cancer prevention. We examined the association between use of NSAIDs and breast cancer risk in a prospective cohort. METHODS: The Sister Study is a prospective cohort study of women who had a sister(s) with breast cancer. As of December 2013, 2118 incident breast cancers were ascertained from 50,884 women enrolled between 2003 and 2009. Lifetime history of NSAID use was estimated from self-reported data in pill-years, with 1 pill per week for a year equivalent to 1 pill-year. Cox regression models were used to estimate hazard ratios (HRs) of breast cancer in relation to pill-years of use for different NSAIDs, with adjustment for potential confounders. RESULTS: In the full cohort, although there was some evidence that use of non-aspirin, non-COXib NSAIDs was associated with lower breast cancer risk, there was little evidence of overall association for most categories of NSAID use. Among postmenopausal women NSAID use was not associated with reduced risk of breast cancer. However, among premenopausal women there was significantly reduced risk for any NSAID (HR4vs1=0.66, 95% CI: 0.50-0.87) and specifically for aspirin (HR4vs1=0.57, 95% CI: 0.33-0.98), with small, but non-significant reductions in risk for other drug classes. CONCLUSION: Women with a sister with breast cancer are themselves at increased risk and might benefit the most from chemoprevention. Although there was little evidence of protective effect from NSAIDs in the overall cohort of women or among the subset who are postmenopausal, there is intriguing evidence that NSAID use, particularly aspirin, may reduce risk among premenopausal women.
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Anti-Inflamatórios não Esteroides/uso terapêutico , Neoplasias da Mama/epidemiologia , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Linhagem , Pós-Menopausa , Pré-Menopausa , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Irmãos , Inquéritos e QuestionáriosRESUMO
BACKGROUND/PURPOSE: Gastroschisis is a resource-intensive birth defect without consensus regarding optimal surgical and medical management. We sought to determine best-practice guidelines by examining differences in multi-institutional practices and outcomes. METHODS: Site-specific practice patterns were queried, and infant-maternal chart review was retrospectively performed for gastroschisis infants treated at 5 UCfC institutions (2007-2012). The primary outcome was length of stay. Univariate analysis was done to assess variation practices and outcomes by site. Multivariate models were constructed with site as an instrumental variable and with sites grouped by silo practice pattern adjusting for confounding factors. RESULTS: Of 191 gastroschisis infants, 164 infants were uncomplicated. Among uncomplicated patients, there were no deaths and only one case of necrotizing enterocolitis. Bivariate analysis revealed significant differences in practices and outcomes by site. Despite wide variations in practice patterns, there were no major differences in outcome among sites or by silo practice, after adjusting for confounding factors. CONCLUSIONS: Wide variability exists in institutional practice patterns for infants with gastroschisis, but poor outcomes were not associated with expeditious silo or primary closure, avoidance of routine paralysis, or limited central line and antibiotic durations. Development of clinical pathways incorporating these practices may help standardize care and reduce health care costs.
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Gerenciamento Clínico , Nutrição Enteral/métodos , Gastroplastia/métodos , Gastrosquise/terapia , Prática Institucional , Universidades/estatística & dados numéricos , California , Feminino , Humanos , Recém-Nascido , Masculino , Estudos RetrospectivosRESUMO
Analysis of milk from 247 HIV-infected Zambian mothers showed that galectin-3 binding protein concentrations were significantly higher among HIV-infected mothers who transmitted HIV through breast-feeding (6.51 ± 2.12 µg/mL) than among nontransmitters but were also correlated with higher milk and plasma HIV RNA copies/mL and lower CD4+ cell counts. The association between galectin-3 binding protein and postnatal transmission was attenuated after adjustment for milk and plasma HIV load and CD4+ cell counts. This suggests that although milk galectin-3 binding protein is a marker of advanced maternal disease, it does not independently modify transmission risk.
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Antígenos de Neoplasias/análise , Biomarcadores Tumorais/análise , Aleitamento Materno , Proteínas de Transporte/análise , Glicoproteínas/análise , Infecções por HIV/transmissão , Transmissão Vertical de Doenças Infecciosas , Leite Humano/química , Leite Humano/virologia , Estudos de Casos e Controles , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/metabolismo , Humanos , Fatores de Risco , Carga Viral , Zâmbia/epidemiologiaRESUMO
The process of wound healing is complicated and requires optimization of wound bed conditions locally through wound management and systemically through proper nutritional care. Although there are a variety of local and systemic factors that can adversely influence healing, the wound environment can be treated through proper dressings to decrease necrotic debris, bacterial load, and foreign bodies. In addition, maintaining or improving patient nutritional status will help the body to supply the necessary building blocks and cellular response for healing to take place.
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Terapia Nutricional/métodos , Cicatrização/fisiologia , Ferimentos e Lesões/terapia , Infecções Bacterianas/prevenção & controle , Bandagens , Proliferação de Células , Colágeno/fisiologia , Citocinas/fisiologia , Corpos Estranhos/prevenção & controle , Hemostasia/fisiologia , Humanos , Inflamação/fisiopatologia , Mediadores da Inflamação/fisiologia , Necrose , Estado NutricionalRESUMO
BACKGROUND: Silibinin, a natural polyphenolic flavonoid, has been reported to induce cell death in various cancer cell types. However, the molecular mechanism is not clearly defined. Our previous study showed that silibinin induces glioma cell death and its effect was effectively prevented by calpain inhibitor. The present study was therefore undertaken to examine the role of calpain in the silibinin-induced glioma cell death. METHODS: U87MG cells were grown on well tissue culture plates and cell viability was measured by MTT assay. ROS generation and â³ψm were estimated using the fluorescence dyes. PKC activation and Bax expression were measured by Western blot analysis. AIF nuclear translocation was determined by Western blot and immunocytochemistry. RESULTS: Silibinin induced activation of calpain, which was blocked by EGTA and the calpain inhibitor Z-Leu-Leu-CHO. Silibinin caused ROS generation and its effect was inhibited by calpain inhibitor, the general PKC inhibitor GF 109203X, the specific PKCδ inhibitor rottlerin, and catalase. Silibinin-induce cell death was blocked by calpain inhibitor and PKC inhibitors. Silibinin-induced PKCδ activation and disruption of â³ψm were prevented by the calpain inhibitor. Silibinin induced AIF nuclear translocation and its effect was prevented by calpain inhibitor. Transfection of vector expressing microRNA of AIF prevented the silibinin-induced cell death. CONCLUSIONS: Silibinin induces apoptotic cell death through a calpain-dependent mechanism involving PKC, ROS, and AIF nuclear translocation in U87MG human glioma cells.
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Antioxidantes/farmacologia , Fator de Indução de Apoptose/metabolismo , Apoptose/efeitos dos fármacos , Calpaína/metabolismo , Núcleo Celular/metabolismo , Silimarina/farmacologia , Calpaína/antagonistas & inibidores , Morte Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Glioma/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteína Quinase C/metabolismo , Transporte Proteico/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Silibina , Proteína X Associada a bcl-2/metabolismoRESUMO
Persistent pulmonary hypertension (PPHN) of the newborn remains a challenging condition to diagnose and treat. It has been reported in infants with Smith-Lemli-Opitz syndrome (SLOS), a rare defect in cholesterol synthesis. Typically, there is evidence of pulmonary hypoplasia. We report the first case of PPHN in the absence of pulmonary hypoplasia or other parenchymal diseases in an infant with SLOS. Perturbations in cholesterol metabolism interrupt key signaling pathways that participate in the normal maintenance of pulmonary vascular tone. We found that caveolae-dependent signaling may be involved in this process since our patient had altered expression of caveolin-1.
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Síndrome da Persistência do Padrão de Circulação Fetal/complicações , Síndrome de Smith-Lemli-Opitz/diagnóstico , Caveolina 1/metabolismo , Evolução Fatal , Humanos , Imuno-Histoquímica , Recém-Nascido , Pulmão/metabolismo , Masculino , Síndrome da Persistência do Padrão de Circulação Fetal/diagnóstico , Síndrome da Persistência do Padrão de Circulação Fetal/metabolismo , Síndrome de Smith-Lemli-Opitz/metabolismoRESUMO
Development of cancer therapeutics requires a thorough evaluation of drug efficacy in vitro before animal testing and subsequent clinical trials. Three-dimensional (3-D) in vitro models have therefore been investigated for drug screening. In this study, we have developed a novel in vitro model in which multicellular aggregates, or spheroids, were incorporated into 3-D porous scaffolds. Drug resistance assays showed that spheroid-seeded scaffolds have much higher drug resistance than monolayer cultures, spheroids on flat substrates, or scaffolds seeded with dispersed cells. Furthermore, spheroid-seeded scaffolds demonstrated higher lactate production leading to acidosis, and higher expression of angiogenic factors. These data suggest that the spheroid-seeded 3-D scaffolds might serve as a useful in vitro system for screening cancer therapeutics.
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Ensaios de Seleção de Medicamentos Antitumorais/métodos , Esferoides Celulares/efeitos dos fármacos , Alicerces Teciduais , Células Tumorais Cultivadas/efeitos dos fármacos , Humanos , Esferoides Celulares/citologia , Células Tumorais Cultivadas/citologiaRESUMO
Collagenase purified from bacteria has been used to isolate islets for transplantation. However, collagenase is contaminated with small amounts of endotoxin, which induces dysfunction or apoptosis of islets. In this study, we investigated the effects of polymyxin B, endotoxin scavenger, on the yield and quality of isolated islets. It is revealed that polymyxin B neutralized endotoxin in vitro and inhibited endotoxin-mediated decreases of the glucose stimulation index. Additionally, adenosine triphosphate (ATP) quantitation, islet regression assay, and caspase-3 activation assay demonstrated that polymyxin B efficiently blocked the toxic effects induced by endotoxin. Thereafter, we isolated mouse islets both with and without polymyxin B and compared total islet equivalents (IEQs), glucose-stimulated insulin release, and ATP content. Polymyxin B enhanced islet recovery, and ATP content of islets, and glucose stimulation index, and reduced TNF-alpha expression of islets. Marginal transplantation (200 IEQs/mouse) under the kidney capsule of diabetic mice induced normoglycemia in 30% of the polymyxin B group, but not in any mouse of control group. This result suggests that islets isolated with polymyxin B more effectively lower blood glucose levels as compared with control islets. Thus, polymyxin B could serve as a useful agent in the protection of islets from endotoxin-induced inflammation and apoptosis.
Assuntos
Endotoxinas/antagonistas & inibidores , Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/efeitos dos fármacos , Polimixina B/farmacologia , Animais , Apoptose/efeitos dos fármacos , Sequência de Bases , Glicemia/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/fisiopatologia , Diabetes Mellitus Experimental/cirurgia , Endotoxinas/toxicidade , Técnicas In Vitro , Inflamação/prevenção & controle , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/fisiologia , Transplante das Ilhotas Pancreáticas/patologia , Transplante das Ilhotas Pancreáticas/fisiologia , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transplante Isogênico , Fator de Necrose Tumoral alfa/genéticaRESUMO
Human mesenchymal stem cells (hMSCs) represent a potent target for gene delivery for both stem cell differentiation applications and clinical therapies. However, it has, thus far, proven difficult to develop delivery vehicles that increase the efficiency of gene delivery to hMSCs, due to several problematic issues. We have evaluated different vehicles with regard to the efficiency with which they deliver hMSCs and enhance the ability to deliver a reporter gene. In this study, a non-viral gene delivery system using nanoparticles was designed, with emphasis placed on the ability of the system to mediate high levels of gene expression into stem cells. Via polyplexing with polyethylenimine (PEI), the cell-uptake ability of the nanoparticles was enhanced for both in vitro and in vivo culture systems. In experiments with PEI/pNDA polyplexed with nanoparticles, the expression of green fluorescent protein (GFP) with this vehicle was noted in up to 75% of hMSCs 2 days after transfection, and GFP gene expression was detected via Western blotting, flow cytometric analysis, and immunofluorescence using a confocal laser microscope after transfection.
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DNA/administração & dosagem , Vetores Genéticos , Células-Tronco Mesenquimais/metabolismo , Nanopartículas , Adulto , Animais , Western Blotting , Terapia Genética , Humanos , Masculino , Camundongos , Microscopia Eletrônica de TransmissãoRESUMO
We explored whether adipocyte culture medium affects the secreted chemokine profile of tumor cells, because adipocytes stimulate progression or metastasis of breast cancer cells, and chemokines secreted from tumor cells are involved in these processes. CCL20 expression was dramatically increased, and an NF-kappaB blocker completely inhibited adipocyte culture medium-induced CCL20 expression in MDA-MB-231 cells. We showed that adipocyte culture medium increased the production of TNF-alpha in MDA-MB-231 cells, which stimulated CCL20 expression in an autocrine fashion. Our data also showed that CCL20 increased the migration and invasiveness of MDA-MB-231 cells, but did not affect the proliferation of these cells.
Assuntos
Adipócitos/citologia , Quimiocina CCL20/biossíntese , Fator de Necrose Tumoral alfa/metabolismo , Tecido Adiposo/metabolismo , Animais , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Quimiocinas/metabolismo , Meios de Cultura/farmacologia , Progressão da Doença , Humanos , Camundongos , Invasividade Neoplásica , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
BACKGROUND: Except for tyrosine, the amino acid requirements of human neonates receiving parenteral nutrition (PN) have not been experimentally derived. OBJECTIVES: The objectives were to determine the total sulfur amino acid (TSAA) requirement (methionine in the absence of cysteine) of postsurgical, PN-fed human neonates by using the indicator amino acid oxidation (IAAO) technique with L-[1-(13)C]phenylalanine as the indicator. DESIGN: Fifteen postsurgical neonates were randomly assigned to receive 1 of 18 methionine intakes ranging from 10 to 120 mg x kg(-1) x d(-1), delivered in a customized, cysteine-free amino acid solution. Breath and urine samples were collected for the measurement of (13)CO(2) and amino acid enrichment. Blood samples were collected at baseline and after the test methionine infusion for the measurement of plasma methionine, homocysteine, cystathionine, and cysteine concentrations. RESULTS: Breakpoint analysis determined the mean TSAA requirements to be 47.4 (95% CI: 38.7, 56.1) and 49.0 (95% CI: 39.9, 58.0) mg x kg(-1) x d(-1) with the use of oxidation and F(13)CO(2), respectively. CONCLUSIONS: This is the first study to report the TSAA requirement of postsurgical, PN-fed human neonates. The estimated methionine requirement expressed as a proportion of the methionine content of current commercial pediatric PN solutions was 90% (range: 48-90%) of that found in the lowest methionine-containing PN solution.